Biotin complexes for treatment and diagnosis of Alzheimer'S disease

Abstract

Described herein are compositions and methods for treating or imaging Alzheimer's disease (AD). The compositions comprise a biotin moiety and a siRNA moiety, without the need for a targeting agent such as an antibody, avidin, or streptavidin. In certain embodiments, the compositions further comprise a diagnostic agent.

I claim: 
     
       1. A composition comprising a biotin moiety and a siRNA moiety, wherein the siRNA moiety comprises a nucleotide of SEQ ID NO: 2 or a nucleic acid that has at least 95% sequence homology with SEQ ID NO: 2. 
     
     
       2. The composition of  claim 1 , wherein the composition further comprises a linker between the siRNA and the biotin. 
     
     
       3. The composition of  claim 1 , wherein the composition does not comprise an antibody, an antigen, avidin, or streptavidin. 
     
     
       4. The composition of  claim 1 , wherein the composition further comprises a diagnostic agent. 
     
     
       5. The composition of  claim 4 , wherein the diagnostic agent is selected from the group consisting of a fluorophore, a chromophore, a chemoluminescing agent, a radionuclide, an unpair spin atom, a free radical, and a contrast agent. 
     
     
       6. The composition of  claim 1 , wherein the composition is able to transfect cells in vivo. 
     
     
       7. The composition of  claim 1 , wherein the composition partially, substantially, or completely deletes, silences, inactivates, interferes with, or down-regulates a gene that encodes selenoprotein P. 
     
     
       8. The composition of  claim 1 , wherein the siRNA moiety comprises a guanosine at the 5′-end. 
     
     
       9. The composition of  claim 1 , wherein the sense or the antisense strand of the siRNA moiety is equal to or less than 30 nucleotides in length. 
     
     
       10. A pharmaceutically acceptable formulation, wherein the pharmaceutically acceptable formulation comprises a therapeutically-effective amount of a composition of  claim 1  and a pharmaceutically acceptable carrier or diluent. 
     
     
       11. A method generating an image of a subject, comprising the steps of:
 administering to a subject in need of imaging a detectable amount of a composition of  claim 4 , and 
 generating an image. 
 
     
     
       12. The method of  claim 11 , wherein said subject is a human.